1. Field of the Invention
The present invention relates to an electric device testing apparatus for testing an electric device, such as an IC chip, under a predetermined temperature, more specifically relates to an electric device testing apparatus which can always maintain the temperature around the electric device at a set temperature even when the electric device itself generates heat during the test and perform testing electric devices at a desired set temperature with a high credibility.
2. Description of the Related Art
A testing apparatus for testing a finally produced device, such as an IC chip, is necessary in a producing process of a semiconductor device, etc. As one kind of such testing apparatuses, an apparatus for testing an IC chip under applying a thermal stress of a high temperature, a normal temperature and a lower temperature than a normal temperature is known. It is because IC chips are required to guarantee as a feature thereof to operate well under a high, normal and low temperature.
A test is carried out in such a testing apparatus, wherein an upper portion of its test head is covered with a chamber for providing a sealed space, an IC chip is conveyed to above the test head, where the IC chip is pushed against the test head for connection, and inside the chamber is maintained at a high, normal or low temperature condition within a constant temperature range. The IC chips are preferably tested by the above test and sorted into at least good ones and defective ones.
Along with the recent IC chips becoming higher to speed and more highly integrated, however, the heat generation by itself during operating has become higher and heat is generated by itself also during the IC chip testing. Even when inside the chamber is maintained at a constant temperature, it has become difficult to carry out the test on an IC chip under the original temperature of the test. For example, some generates about 30 watts of heat by itself depending on kinds of the IC chips.
When testing an IC chip which generates such high heat by itself, the temperature around the IC chip rises due to the self heating even if inside the chamber is made to be at a constant temperature, so it becomes difficult to carry out a test on the IC chip under a determined testing temperature. When a test of an IC chip cannot be carried out under a determined testing temperature, it gives a problem that reliability of the test declines.
Especially, when the self heating of an IC chip is high in a high temperature test, assuming that though a set temperature inside a chamber is 80xc2x0 C., the actual temperature on the IC chip device becomes 90xc2x0 C. Thus, the temperature on the device becomes rather higher than the set temperature. Also, when a high temperature test of about 125xc2x0 C. is carried out, for example, the quantity of heat by the self heating in addition to that of the set temperature is applied to the IC chip, as a result, there arises a possibility that the temperature on the IC chip exceeds its tolerable limit.
Thus, in the related art, a correction value (10xc2x0 C.) is determined in advance by expecting the self heating of the IC chip to set the set temperature of inside the chamber at 70xc2x0 C., which is 10xc2x0 C. lower than the test temperature of 80xc2x0 C. in the specification. By doing so, tests have been carried out assuming that the temperature on the IC chip during the test is set at 80xc2x0 C. as in the test specification.
However, when the self heating is very high due to high integration of an IC chip or when a test time is long, it is difficult to determine the correction value in advance and to precisely control the test temperature of a device under the test, such as an IC chip.
An object of the present invention is to provide an electric device testing apparatus which can always maintain the temperature around the electric device at a set temperature even if the electric device under testing generates heat by itself during the test so as to carry out a test on the electric device under a desired temperature with high credibility, and furthermore, prevent the electric device from being damaged.
(1) To attain the above object, according to a first aspect of the present invention, there is provided an electric device testing apparatus comprising:
a connection terminal to which an electric device to be tested is removably connected;
a pusher for pushing the electric device against said connection terminal in order to connect the electric device to said connection terminal;
and a means for adjusting a temperature of the electric device during a test on said electric device via a hole formed on said pusher.
(1-1) In this case, it is preferable that the hole includes a ventilation hole formed on said pusher, and the temperature adjusting means includes a temperature adjusted gas supply means for blowing a temperature adjusted gas to around said electric device during the test on the electric device.
Also, it is preferable that the temperature adjusted gas supply means includes a temperature ventilation amount control means for controlling the temperature of the temperature adjusted gas and/or the ventilation amount to be supplied around the electric device during the test on the electric device based on temperature data from a temperature sensor.
Also, it is preferable that the temperature adjusted gas supply means includes a dry means for previously drying the temperature adjusted gas to be supplied around the electric device.
Furthermore, it is preferable that the electric device testing apparatus according to the present invention further comprises a sealed chamber for covering said connection terminal, pusher and electric device as one.
Also, it is preferable that the temperature adjusted gas to be supplied around the electric device from the temperature adjusted gas supply means is an air taken out from a part of the air inside said chamber and being adjusted its temperature.
When performing a high temperature test, normal temperature test, or low temperature test on an electric device, such as an IC chip, the electric device becomes high temperature due to its self-heating and the temperature around the electric device becomes higher than a set temperature in a usual case. However, in an electric device testing apparatus according to the present invention, a temperature adjusted gas is directly blown around the electric device via a ventilation hole formed on a pusher. The temperature adjusted gas is, for example, a dry air and set, for example, at a temperature specified in the test specification, or at a temperature of being added a control value to the temperature. For example, when the test specification specifies a high temperature test of 80xc2x0 C., the temperature adjusted air is at 80xc2x0 C. or less in order to maintain the electric device under the test at 80xc2x0 C. and blown directly around the electric device. Note that during the test, by detecting the temperature on the electric device, the temperature and/or amount of the temperature adjusted gas are adjusted so that the electric device becomes at the temperature specified in the test specification. The adjustment of the temperature and/or the blowing amount are preferably performed for individual electric device. It is because even if the electric devices to be tested are all identical, the temperature may vary depending on the position of the electric device inside the chamber.
As explained above, an electric device testing apparatus according to the present invention, electric devices are always tested under a condition close to a set temperature (temperature specified in a test specification), and the reliability of the test improves.
In the above invention, it is preferable that the pusher is provided with a temperature sensor capable of detecting an temperature of the electric device and/or an atmosphere temperature around the electric device.
By detecting by the temperature sensor the temperature on the electric device and/or the atmosphere temperature around the electric device and controlling the temperature and/or blowing amount of the blowing gas based on the temperature data from the temperature sensor, temperature controlling can be stable and uniform, unnecessary blowing(ventilation) is eliminated, and it contributes to energy saving.
(1-2) Furthermore, it is preferable that the hole includes a drawing hole formed on the pusher, and the temperature adjusting means includes an air drawing means for drawing an air around the electric device during the test on the electric device.
In this case, it is preferable that the drawing means includes a drawing amount control means for controlling the drawing amount of the air around the electric device during the test on the electric device based on the temperature data from the temperature sensor.
Also, it is preferable that the electric device testing apparatus according to the present invention further comprises a chamber for maintaining the atmosphere temperature constant around the connection terminal to which said electric device is removably connected.
When performing a high temperature test, normal temperature test, or low temperature test on an electric device, such as an IC chip, the electric device becomes high temperature due to its self-heating and the temperature around the electric device becomes higher than a set temperature in a usual case. However, in an electric device testing apparatus according to the present invention, the atmosphere gas around the electric device which has become a higher temperature than a set temperature due to the self-heating is drawn by a drawing means. Therefore, the atmosphere gas around the electric device is always drawn to be discharged and the heat caused by the self-heating is taken away, and an air adjusted to be the set temperature is flown around the electric device, instead. As a result, the electric device is always tested under the condition close to a set temperature and the reliability of the test improves.
In the above invention, it is preferable that the pusher is provided with a temperature sensor capable of detecting an temperature of the electric device and/or an atmosphere temperature around the electric device.
By detecting by the temperature sensor the temperature on the electric device and/or the atmosphere temperature around the electric device and controlling the drawing amount based on the temperature data from the temperature sensor, temperature controlling can be stable and uniform, unnecessary blowing(ventilation) is eliminated, and it contributes to energy saving.
(1-3) The above invention can be implemented as an electric device testing apparatus comprising:
an adaptor to which the pusher is fixed;
a match plate for elastically holding the adaptor;
and a drive plate having a pushing portion for detachably contacting the upper surface of the adaptor and for moving the pusher in the direction of the connection terminal; and
wherein:
the match plate is arranged on the connection terminal changeably in accordance with a kind of the electric device;
the drive plate is arranged movably upward and downward at the upper portion of the match plate; and
a first hole formed on the pusher is configured to be connected to a second hole formed on the adaptor, and the second hole formed on the adaptor is configured to be able to connect to a third hole formed on a pushing portion of the drive plate.
In this case, it is preferable that the sealing member for sealing a connection portion of the holes to each other is provided to a contact portion of the pushing portion of the drive plate and the adaptor.
(2) To attain the above object, according to the second aspect of the present invention, there is provided an electric device testing apparatus, comprising: a suction head for picking up an electric device; a suction force giving means for giving the suction force to said suction head; and a suction force crushing means for releasing the suction force of said suction head; for performing a test by pushing a terminal of said electric device to be tested against a connection terminal of a test head;
and for blowing fluid for releasing the suction force of said suction head on the electric device pushed against the suction head for any period of time during the test on the electric device.
When releasing the electric device picked up by the suction head, it is often the case that the electric device is not smoothly released only by stopping applying the suction force. This problem becomes more obvious when the electric device is smaller and lighter. Therefore, there is provided a suction force crush means for releasing the suction force on the electric device held by the suction head by coercively flows the fluid for suction, such as an air, backward, as a result, the electric device can be smoothly released.
In the present invention, by utilizing the suction force crush means, since the fluid for releasing the suction force of the suction head on the electric device to be tested which is pushed against the suction head exactly for at least any period of time during the test, the self-heating generated during the test can be released. As a result, it is possible to prevent the electric device from being broken or damaged due to excessive heating, which is especially regarded as a problem in a high temperature test.
Furthermore, raising of the temperature by self-heating is suppressed by blowing a fluid, it is not limited to a high temperature test, but a test can be performed at a desired accurate temperature and the reliability of the test results improves.
(2-1) In the above invention, though it is not specifically limited, it is preferable that the electric device testing apparatus further comprises a chamber for maintaining the atmosphere temperature constant around the connection terminal.
When the present invention is applied to an electric device testing apparatus of a type of applying a predetermined temperature on an electric device by maintaining the atmosphere temperature inside the chamber constant, the above efficiencies become more remarkable.
(2-2) In the above invention, though it is not specifically limited, it is preferable that a suction surface of the suction head is formed a groove in which the fluid can passes through.
The cooling effect on the electric device is promoted by flowing a fluid in the grooves formed on the suction surface, and the above effects of suppressing the temperature rising caused by the self-heating becomes more remarkable. Furthermore, if the effects of suppressing the temperature rising improves, it becomes possible to cool with a small amount of fluid or shorter time of fluid blowing.
(2-3) In the above invention, an operation instruction for blowing the fluid is not specifically limited, however, it is preferable that blowing of the fluid on the electric device is performed by sending an instruction signal from a control means to the suction force crush means.
The suction force giving means and suction force crush means are controlled for picking up to hold or releasing the electric device on or from the suction head. However, by using the control means to control the control in common or by providing another control means, it is possible to blow a fluid.
(2-4) In the above invention, the temperature of the blown fluid is not specifically limited, however, it is preferable that the electric device testing apparatus further comprises a temperature control unit for controlling the fluid to be blown on the electric device to be a predetermined temperature.
By controlling the temperature of the fluid blown to the electric device at a predetermined temperature, the above cooling effects can be more effectively present.
(2-5) In the above invention, the specific configuration of the suction force giving means is not specifically limited, however, it is preferable that the suction force giving means includes a fluid supply source, an ejector connected to the suction head, an ejector valve comprised by the fluid supply source, the ejector and the suction head.
Namely, by supplying a fluid, such as an air, from the fluid supply source to the ejector, the electric device can be held on the suction head. The on/off of the suction force is switched by opening/closing of the ejector valve.
Also, in the above invention, the specific configuration of the suction force crush means is not specifically limited, however, it is preferable that the suction force crush means includes a fluid supply source and a crush valve connected to the fluid supply source and the suction head.
Namely, by supplying a fluid, such as an air, from the fluid supply source to the suction head, since the fluid flows at the suction head in the opposite direction to the suction force, even small light electric devices can be surely and correctly released. The on/off of the releasing is switched by opening/closing of the crush valve.
(2-6) In the above invention, it is not specifically limited, however, it is characterized that the fluid supply source of the suction force giving means and the fluid supply means of the suction force crush means are identical fluid supply means. By this, the fluid supply circuit can be simplified and the cost can be reduced.
Also, it is not specifically limited, however, it is preferable that the fluid to be blown on the electric device is commonly used as fluid applied to the suction force giving means.
(2-7) In the above invention, kinds of the fluid is not specifically limited, however, an air is preferable when considering the easy handling and a low cost.
(3) To attain the above object, according to the third aspect of the present invention, there is provided an electric device testing apparatus comprising a suction head for picking up an electric device, a suction force giving means for giving a suction force to the suction head, and a suction force crush means for releasing the suction force of the suction head; for holding and releasing said electric device; and
for blowing fluid on the electric device for releasing the suction force of the suction head when the electric device is held at a fixed position.
In this case, it is preferable that the suction surface of the suction head is formed a groove in which the fluid can pass through.
Further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.